Comparação da eficácia de limpeza entre o sistema FKG race e instrumentos manuais em molares inferiores

INTRODUCTION AND OBJECTIVE: The aim of this study was to evaluate the ability of root canal cleaning of the RaCe rotary instrumentation system (FKG Dentaire - La-Cheaux-de Fonds - Switzerland), compared to manual filing with Stainless Steel K-files (Maillefer Instruments - Ballaigues - Switzerland). MATERIAL AND METHOD: Twenty extracted human teeth (maxillary molars) were selected and their pulp tissue was removed after coronal access. The root canals were filled with a dye (India ink) and allowed to dry for 48 hours, followed by establishment of the working length of the mesiobuccal root; then, half of the specimens were instrumented by the modified Oregon technique and the other half were instrumented by crown-down sequence of the RaCe system. After preparation, the teeth were longitudinally sectioned and evaluated according to the amount of remaining dye. RESULTS: Data obtained were registered as numerical scores, and the arithmetic means were compared between groups using the Mann Whitney test. Both techniques were unable to completely clean the interior of the root canals, with a better performance of the manual technique only at the middle third. CONCLUSION: It could be concluded that the RaCe system was able to provide satisfactory cleaning, similar to that obtained by the manual instrumentation technique.Objetivo deste trabalho foi avaliar a capacidade de limpeza de canais radiculares por meio do sistema de instrumentação RaCe (FKG Dentaire - La-Cheaux-de Fonds - Suíça) em comparação à instrumentação manual por meio de limas tipo K-File (Maillefer Instruments - Ballaigues - Suíça). Foram selecionados 20 dentes humanos extraídos (molares superiores) que tiveram seu conteúdo radicular removido após realização da abertura coronária. Os canais foram preenchidos com corante (tinta nanquim) e após 48 horas para secagem, realizou-se a odontometria da raiz mésio-vestibular. Metade dos espécimes foi instrumentada pela técnica de Oregon modificada e a outra metade pela seqüência crown-down preconizada pelo fabricante do sistema RaCe. Após o preparo, os dentes foram seccionados longitudinalmente e avaliados de acordo com a quantidade de corante remanescente. Os dados obtidos foram registrados por meio de escores numéricos e as médias aritméticas foram analisadas entre os grupos pelo teste de Mann Whitney. Ambas as técnicas foram incapazes de limpar completamente o interior dos canais radiculares sendo que a técnica manual desempenhou limpeza significantemente superior apenas no terço médio. Conclui-se que o sistema RaCe foi capaz de desempenhar uma limpeza satisfatória sendo próxima àquela conseguida pela técnica de instrumentação manual

Domestic dog invasion in an agroforestry \ud mosaic in southern Bahia, Brazil

Although the value of agroforests for biodiversity conservation has been frequently highlighted, little is known about the \ud susceptibility of this production system to biological invasions. Drawing on a camera-trap dataset obtained in 39 sites in an \ud agroforestry mosaic in southern Bahia, Brazil, we investigated whether the conversion of native forests into agroforests and \ud management intensification in agroforests favor the invasion by the most common carnivore worldwide, the domestic dog. We \ud also examined whether domestic dog invasion is more associated with human activity in agroforests than in native forests. While \ud the number of invading dogs was higher in agroforests than in native forests (11 compared to 7 dogs per site), management \ud intensification in agroforests led to a higher mean number of visits per dog. In both habitats (not only agroforests) visits by \ud domestic dogs tended to be concentrated on times of the day (around midday) and days of the week (Monday to Saturday) when \ud there is greater human activity. Despite being permeable to native species, agroforests may act as sink or trap areas given their \ud higher susceptibility to invasion, potentially limiting the value of this production system for biodiversity conservation. Moreover, \ud local management intensification, which has been expanding worldwide, increases the intensity of such invasions, further \ud decreasing the value of agroforests. The value of agroforestry mosaics for conservation thus depends on the management of \ud invasive species and at least in the case of dogs, one of the most common and widely distributed invasive species, this \ud management should focus on the habits and behavior of humans.EF was granted a MSc scholarship and CRC a PhD scholarship from FAPESP (2011/03113-5 and 2007/54888-1, respectively), and RP had a research fellowship from CNPq (306715/2011-2) during the development of this wor

Responses of five small mammal species to micro-scale variations in vegetation structure in secondary Atlantic Forest remnants, Brazil

<p>Abstract</p> <p>Background</p> <p>The Brazilian Atlantic Forest is highly endangered and only about 7% of the original forest remains, most of which consists of fragments of secondary forest. Small mammals in the Atlantic Forest have differential responses to this process of fragmentation and conversion of forest into anthropogenic habitats, and have varying abilities to occupy the surrounding altered habitats. We investigated the influence of vegetation structure on the micro-scale distribution of five small mammal species in six secondary forest remnants in a landscape of fragmented Atlantic Forest. We tested whether the occurrence of small mammal species is influenced by vegetation structure, aiming to ascertain whether species with different degrees of vulnerability to forest fragmentation (not vulnerable: <it>A. montensis</it>, <it>O. nigripes </it>and <it>G. microtarsus</it>; vulnerable: <it>M. incanus </it>and <it>D. sublineatus</it>; classification of vulnerability was based on the results of previous studies) are associated with distinct vegetation characteristics.</p> <p>Results</p> <p>Although vegetation structure differed among fragments, micro-scale distribution of most of the species was influenced by vegetation structure in a similar way in different fragments. Among the three species that were previously shown not to be vulnerable to forest fragmentation, <it>A. montensis </it>and <it>G. microtarsus </it>were present at locations with an open canopy and the occurrence of <it>O. nigripes </it>was associated to a low canopy and a dense understory. On the other hand, from the two species that were shown to be vulnerable to fragmentation, <it>M. incanus </it>was captured most often at locations with a closed canopy while the distribution of <it>D. sublineatus </it>was not clearly influenced by micro-scale variation in vegetation structure.</p> <p>Conclusion</p> <p>Results indicate the importance of micro-scale variation in vegetation structure for the distribution of small mammal species in secondary forest fragments. Species that are not vulnerable to fragmentation occurred at locations with vegetation characteristics of more disturbed forest, while one of the species vulnerable to fragmentation was found at locations with older forest characteristics. Results suggest that micro-habitat preferences may be an important factor influencing the capacity of small mammals to occupy altered habitats and, consequently, their vulnerability to forest fragmentation at a larger spatial scale.</p

Coin finds from archaeological sites in Campania: a new portal for documentation and research

At the University of Salerno, the CFH (Coin Finds Hub) portal on coin finds is being set up in collaboration with several Italian and foreign institutions. In addition to describing its contents, the authors illustrate the first elements emerged from the study of coins from the excavations currently under study, the cataloguing of which will feed into the portal’s database. The sites investigated are Naples, Pompeii, Paestum, and Velia: for each of them, insights related to sample cases are presented. As is usual for those working on coins finds, the most interesting aspects concern the uses of small change, the most used and therefore lost and unrecovered, for which an extensive statistical survey is now available. The comparison of coin finds from different urban communities leads one to reason about how much and to what extent the overlapping or non-overlapping of modern cities with archaeological sites has affected the quality and quantity of numismatic data available; as also the potential for interpreting the incidence of coinage in economic activities

Influência da penetração de instrumentos, empregados na condensação lateral ativa, na qualidade da obturação de canais radiculares

PURPOSE: the purpose of this study was to compare the quality of the obturation and the difference of penetration depth inside the root canal of the instruments Finger Spreader, file type Kerr, Flexofile and Nitiflex when used as spreaders during the filling by Active Lateral Condensation Technique. MATERIAL AND METHOD: 40 extracted permanent human teeth were instrumented by the Modified Goerig Technique and divided in four groups. In the group I the finger spreader was used; in the group II, files type Kerr was used; in the group III, files Flexofile was used and, in the group IV, files Nitiflex, all number 30, for space opening for placement of the secondary cones, during the Technique of Active Lateral Condensation. The radiographic quality of the obturation and the depth of penetration of the instruments was evaluated and analysed statisticaly (Kruskal-Wallis and Dunn's Test). RESULTS AND CONCLUSION: with relationship to the radiograph analysis of the quality of the filling, the group II was what it presented the best result, followed by the groups I, IV and III, respectively. In relation to the depth of penetration of the instruments, the group IV approached more the desired distance, or, 1 millimeter less than the length of the work, followed, respectively, by groups II, III and I.OBJETIVO: comparar a qualidade da obturação e a diferença de profundidade de penetração, no interior do canal radicular, dos espaçadores digitais (Finger Spreader), limas tipo Kerr, Flexofile e Nitiflex, quando utilizados como espaçadores, durante a obturação pela Técnica da Condensação Lateral Ativa. MATERIAL E MÉTODOS: foram utilizados 40 dentes molares permanentes humanos, extraídos, instrumentados pela Técnica de Goerig Modificada e divididos em quatro grupos. No grupo I foi utilizado o espaçador digital C; no grupo II, lima tipo Kerr; no grupo III, lima Flexofile e, no grupo IV, lima Nitiflex, todos com diâmetro (D1) ou diâmetro da ponta correspondente ao diâmetro de uma lima 30 (0,30mm), para abertura de espaço para colocação dos cones secundários, durante a Técnica da Condensação Lateral Ativa. Avaliou-se e submeteu-se à análise estatística (Kruskal-Wallis e teste de Dunn) a qualidade radiográfica da obturação e a profundidade de penetração dos instrumentos. RESULTADOS E CONCLUSÃO: quanto à análise radiográfica da qualidade da obturação, o grupo II foi o que apresentou o melhor resultado, seguido dos grupos I, IV e III, respectivamente. Em relação à profundidade de penetração dos instrumentos, o grupo IV aproximou-se mais da distância desejada, ou seja, 1 milímetro aquém do comprimento de trabalho, seguido, respectivamente, dos grupos II, III e I

Assessing the utility of statistical adjustments for imperfect detection in tropical conservation science

1. In recent years, there has been a fast development of models that adjust for imperfect detection. These models have revolutionised the analysis of field data, and their use has repeatedly demonstrated the importance of sampling design and data quality. There are, however, several practical limitations associated with the use of detectability models which restrict their relevance to tropical conservation science. 2. We outline the main advantages of detectability models, before examining their limitations associated with their applicability to the analysis of tropical communities, rare species and large-scale datasets. Finally, we discuss whether detection probability needs to be controlled before and/or after data collection. 3. Models that adjust for imperfect detection allow ecologists to assess data quality by estimating uncertainty, and to obtain adjusted ecological estimates of populations and communities. Importantly, these models have allowed informed decisions to be made about the conservation and management of target species. 4. Data requirements for obtaining unadjusted estimates are substantially lower than for detectability-adjusted estimates, which require relatively high detection/recapture probabilities and a number of repeated surveys at each location. These requirements can be difficult to meet in large-scale environmental studies where high levels of spatial replication are needed, or in the tropics where communities are composed of many naturally rare species. However, while imperfect detection can only be adjusted statistically, covariates of detection probability can also be controlled through study design. Using three study cases where we controlled for covariates of detection probability through sampling design, we show that the variation in unadjusted ecological estimates from nearly 100 species was qualitatively the same as that obtained from adjusted estimates. Finally, we discuss that the decision as to whether one should control for covariates of detection probability through study design or statistical analyses should be dependent on study objectives. 5. Synthesis and applications. Models that adjust for imperfect detection are an important part of an ecologist's toolkit, but they should not be uniformly adopted in all studies. Ecologists should never let the constraints of models dictate which questions should be pursued or how the data should be analysed, and detectability models are no exception. We argue for pluralism in scientific methods, particularly where cost-effective applied ecological science is needed to inform conservation policy at a range of different scales and in many different systems

Beyond the Fragmentation Threshold Hypothesis: Regime Shifts in Biodiversity Across Fragmented Landscapes

Ecological systems are vulnerable to irreversible change when key system properties are pushed over thresholds, resulting in the loss of resilience and the precipitation of a regime shift. Perhaps the most important of such properties in human-modified landscapes is the total amount of remnant native vegetation. In a seminal study Andrén proposed the existence of a fragmentation threshold in the total amount of remnant vegetation, below which landscape-scale connectivity is eroded and local species richness and abundance become dependent on patch size. Despite the fact that species patch-area effects have been a mainstay of conservation science there has yet to be a robust empirical evaluation of this hypothesis. Here we present and test a new conceptual model describing the mechanisms and consequences of biodiversity change in fragmented landscapes, identifying the fragmentation threshold as a first step in a positive feedback mechanism that has the capacity to impair ecological resilience, and drive a regime shift in biodiversity. The model considers that local extinction risk is defined by patch size, and immigration rates by landscape vegetation cover, and that the recovery from local species losses depends upon the landscape species pool. Using a unique dataset on the distribution of non-volant small mammals across replicate landscapes in the Atlantic forest of Brazil, we found strong evidence for our model predictions - that patch-area effects are evident only at intermediate levels of total forest cover, where landscape diversity is still high and opportunities for enhancing biodiversity through local management are greatest. Furthermore, high levels of forest loss can push native biota through an extinction filter, and result in the abrupt, landscape-wide loss of forest-specialist taxa, ecological resilience and management effectiveness. The proposed model links hitherto distinct theoretical approaches within a single framework, providing a powerful tool for analysing the potential effectiveness of management interventions

Eficiência de Mercado e Corrupção Organizacional: Estudo dos Impactos Sobre o Valor dos Acionistas

With this study, we evaluated the influence of disclosure of the involvement of organizations in corruption on creating value for shareholders. We chosen four companies that had their names linked to allegations of corruption in the past 10 years. An event study was used to verify if relevant information tends to be immediately reflected in stock prices. We selected 28 events for analysis and we observed negative and positive variations of the securities in relation to the market, in the days before the disclosure, as in most of the 20 days after publication. However, in cumulative terms, there was a rise in prices over time, returning to levels near those observed before advertising the event. The results indicate that the market did not behave efficiently in this analyzed period.Com o presente trabalho, avaliou-se a influência da divulgação do envolvimento de organizações em atos de corrupção sobre a criação de valor para os acionistas. Foram escolhidas 4 companhias que tiveram seus nomes ligados à prática de corrupção nos últimos 10 anos. Foi utilizado o estudo de eventos para verificar se informações relevantes são imediatamente refletidas nos preços das ações. 28 eventos foram selecionados para análise e pode-se observar variações negativas e positivas dos títulos em relação ao mercado, nos dias que antecederam a divulgação, assim como na maioria dos 20 dias após a publicação. Porém, em termos cumulativos, observou-se a elevação das cotações com o passar do tempo, retornando a patamares próximos àqueles observados antes da divulgação do evento. Os resultados indicam que o mercado não agiu eficientemente no período analisado